Toronto police said on Saturday that autopsies are being performed on the bodies of billionaire Barry Sherman and his wife after they were found dead in their home on Friday.
"The circumstances of their death appear suspicious and we are treating it that way," said police Constable David Hopkinson. Police have not yet released further details on their deaths.
In a statement issued Saturday afternoon, the Sherman's four children urged police to conduct a thorough and objective criminal investigation into their parents' deaths.
Toronto Mayor John Tory said: "Police are investigating, and I hope that investigation will be able to provide answers for all of us who are mourning this tremendous loss," he said.
The 75-year-old Sherman began building a pharmaceutical empire with Apotex in 1974. The company undercut name-brand drugs by producing cheaper generic versions.
Their Canadian mansion was recently put up for sale, and their bodies were reportedly found by the real estate agent who called police.
Apotex, which called news of the Shermans' deaths "tragic," was recently implicated in a price-fixing scheme with 17 other drug companies and their subsidiaries.
The company grew to employ more than 11,000 people across the globe, while Sherman amassed a fortune estimated to be at least $3.2 billion (€2.7 billion).
Sherman stepped down as chief executive in 2012 but remained Apotex's executive chairman.
The couple had become known in Canada for their philanthropy, and their deaths sent shock waves through the country's political elite.
Prime Minister Justin Trudeau said he was "saddened by news of the sudden passing."
"Our condolences to their family & friends, and to everyone touched by their vision & spirit," Trudeau wrote on Twitter.
Sherman was an active fundraiser for Prime Minister Trudeau's Liberal party but was criticized for holding a pay-for-access fundraiser in August 2015.
In a statement, Toronto Mayor Tory said he was "shocked and heartbroken" to learn of the deaths, and noted the couple's generous contributions to the city.
Linda Frum, a Canadian Senator, said she was "gutted by the loss" of the couple, just two weeks after presenting a Senate medal "to one of the kindest and most beloved members of Canada's Jewish community."
They were "remarkable people," said Bob Rae, former premier of Ontario province which includes Toronto. "Grappling with this terrible news," he wrote on Twitter.
The couple gave tens of millions of dollars to hospitals, universities and Jewish organizations, CBC reported.
"They were extremely successful in business, but also very, very giving people," Rae told CBC. "It's going to be a very, very big loss."
bik/aw (AP, Reuters, AFP)